Portability	non-portable (requires concurrency)
Stability	provisional
Maintainer	libraries@haskell.org
Safe Haskell	None

Graphics.HGL.Window

Contents

Windows
Drawing in a window
Events in a window
Timer ticks

Description

Windows in a simple graphics library.

Synopsis

Windows

data Window Source

type Title = String Source

Title of a window.

data RedrawMode Source

How to draw in a window.

Constructors

DoubleBuffered	use a double buffer to reduce flicker. You should probably use this for animations.
Unbuffered	draw directly to the window. This runs slightly faster but is more prone to flicker.

openWindowEx Source

Arguments

:: Title	title of the window
-> Maybe Point	the optional initial position of a window
-> Size	initial size of the window
-> RedrawMode	how to display a graphic on the window
-> Maybe Time	the time between ticks (in milliseconds) of an optional timer associated with the window
-> IO Window

General window creation.

getWindowRect :: Window -> IO (Point, Size)Source

The position of the top left corner of the window on the screen, and the size of the window.

closeWindow :: Window -> IO ()Source

Close the window.

Drawing in a window

setGraphic :: Window -> Graphic -> IO ()Source

Set the current drawing in a window.

getGraphic :: Window -> IO Graphic Source

Get the current drawing in a window.

modGraphic :: Window -> (Graphic -> Graphic) -> IO ()Source

Update the drawing for a window. Note that this does not force a redraw.

directDraw :: Window -> Graphic -> IO ()Source

Events in a window

data Event Source

A user interface event.

Notes:

Programmers should assume that the Event datatype will be extended in the not-too-distant future and that individual events may change slightly. As a minimum, you should add a "match anything" alternative to any function which pattern matches against Events.
X11 systems typically have three button mice. Button 1 is used as the left button, button 3 as the right button and button 2 (the middle button) is ignored.

Constructors

Char	a properly translated character, sent after a key press.
Fields char :: Char the character represented by a key combination
Key	occurs when a key was pressed or released.
Fields keysym :: Key representation of the keyboard keys pressed isDown :: Bool if `True`, the button was pressed; otherwise it was released if `True`, the key was pressed; otherwise it was released
Button	occurs when a mouse button is pressed or released.
Fields pt :: Point the position of the mouse cursor after the movement the position of the mouse cursor isLeft :: Bool if `True`, it was the left button isDown :: Bool if `True`, the button was pressed; otherwise it was released if `True`, the key was pressed; otherwise it was released
MouseMove	occurs when the mouse is moved inside the window.
Fields pt :: Point the position of the mouse cursor after the movement the position of the mouse cursor
Resize	occurs when the window is resized.
Closed	occurs when the window is closed.

Instances

Show Event

getWindowEvent :: Window -> IO Event Source

Wait for the next event on the given window.

maybeGetWindowEvent :: Window -> IO (Maybe Event)Source

Check for a pending event on the given window.

Timer ticks

Timers that tick at regular intervals are set up by openWindowEx.

getWindowTick :: Window -> IO ()Source

Wait for the next tick event from the timer on the given window.

getTime :: IO Integer Source

Time in milliseconds since some arbitrary epoch.